1. Field of the Invention
The invention relates in general to eyebolts and, in particular, to fixed eyebolt assemblies, and to eyebolt inventory control methods.
2. Description of the Prior Art
Eyebolts of various configurations have been proposed for various purposes. See, for example, Ake U.S. Des. No. 275,868; Bethea U.S. Des. No. 286,979; Palmer U.S. Des. No. 309,251; Schriever U.S. Des. No. 360,353; Kraine U.S. Des. No. 415,951; and Bohli U.S. Pat. No. 3,866,873, which all relate generally to fixed eyebolts with integral washers and separately provided fasteners that mount generally centrally of the eyebolt structure. Mueller U.S. Pat. No. 3,492,033; Motz U.S. Pat. No. 4,408,941; Seidel U.S. Pat. No. 4,699,410; and Pearl U.S. Pat. No. 6,161,883, all relate generally to mounting studs that are threadably received in both a substrate and the mounting member. Jacobs U.S. Pat. No. 3,595,125; Burke U.S. Pat. No. 4,295,765; Freeman U.S. Pat. No. 5,125,861; Conway U.S. Pat. No. 5,730,245; Hanaway U.S. Pat. No. 5,865,416; Kwon U.S. Pat. No. 5,992,910; and Cooper U.S. Des. No. 172,741, all relate generally to eyebolts wherein a mounting stud is integral with and extends generally centrally from the eye of the eyebolt. Harold et al. U.S. Pat. No. 2,748,646; Mason U.S. Pat. No. 4,090,314; McWhirter U.S. Pat. No. 4,419,785; Bongiovanni et al. U.S. Pat. No. 5,320,193; and Smetz U.S. Pat. No. 5,690,457, all relate generally to eyebolt structures in which separate bolts are employed to secure the eyebolt structures to various substrates. Pearl U.S. Pat. No. 6,161,884, from the swivel hoist ring art, discloses a swivel hoist ring in which a double threaded mounting stud and a skirt with radially projecting arms is proposed. The faces of the radially projecting arms are said to be adapted to being struck with a hammer to tighten the mounting stud. Tsui et al. U.S. Pat. No. 5,056,965, from the tool bushing art, discloses a method of controlling an inventory of tooling bushings by stocking a variety of headless press fit bushings of various lengths, and a few standard bushing heads which can be assembled to the headless bushings as needed.
Fixed eyebolts that are intended to carry substantial loads, either in a lifting or tie-down configuration, frequently require removal and reinstallation in the same or different locations. Typically, special tools to accomplish such removal and reinstallation are not available or are not used. The ability to reliably install or remove an eyebolt manually with only a hammer would be advantageous. In general, fixed eyebolts are not configured to accommodate this situation. Inadequate tightening of an eyebolt to a substrate may result in a safety hazard.
Repeated or improper removal and reinstallation often damages the threads or other mounting elements by which fixed eyebolts are secured to substrates. Damaged eyebolts must be refurbished or replaced. Refurbishment generally requires that the mounting stud or other mounting components be replaced. Thus, the eyebolt body should preferably be separable from the mounting component.
Fixed eyebolts find application in a variety of different applications such as, for example, load tie-downs, load lifting, material handling, and the like. In the construction industry, fixed eyebolts are frequently secured to concrete substrates through, for example, conventional wire thread connections (see, for example the wire thread disclosed in Tsui U.S. Pat. No. 5,732,991). In heavy manufacturing industries, fixed eyebolts are frequently secured to substrates through, for example, machine or square threads. In some industries, various different threads are traditionally used for securing eyebolts to substrates. The eyebolt body is typically the same for a given load capacity, but several different thread styles or even stud diameters must be available to satisfy the requirements of various applications. If the mounting components are made integral with the body of the eyebolt, a different eyebolt is required for each different thread style.
When an eyebolt with an integral mounting component becomes damaged, the entire eyebolt is often discarded. The body of a typical eyebolt is the most expensive part of the assembly, and comprises the majority of the high grade alloy that is used in the device. High strength alloys are sometimes in short supply. The equipment that is required to process high strength alloys requires a considerable capital investment, and operational costs are significant. Minimizing the number of eyebolt bodies that must be made and stocked would significantly reduce the cost of maintaining an inventory of eyebolts. If only one eyebolt body could be stocked for each rated load, regardless of the requirements for multiple different mounting components, the costs and difficulty of maintaining an eyebolt inventory could be significantly reduced. If a particular thread style or stud diameter falls out of favor and is no longer used, all of the fixed eyebolts with these dimensions in which the mounting stud is integral with the eyebolt body must be discarded. Mounting studs can be produced quickly and relatively inexpensively, so it would not be necessary to stock a large number of such studs of any given thread style if the studs were to be made separate from the eyebolt body. The studs can be produced as the demand appears. Inventory costs could be reduced if large numbers of integral eyebolt body-mounting studs with different thread styles did not have to be produced and inventoried to meet anticipated demand.
An eyebolt, even though of a fixed design, should be capable of supporting a rated load applied from any direction. Otherwise, the installer of the eyebolt must be aware of and follow installation instructions as to the necessary orientation of the eyebolt relative to the anticipated load. Even if the installation instructions are known, and they are followed, unexpected shifts in the direction of the applied load may create a safety hazard. The necessity to orient the eye in a particular direction to accommodate a load may result in less than optimum tightening of the eyebolt, thus creating a safety hazard.
These and other difficulties of the prior art have been overcome according to the present invention.